*melanin: the pigment produced by your skin that gives it a tanned colour. 2. Take your time, and build your tan up slowly. Everyone reacts differently to the sun, but here are some guidelines to get you started: If tanning in the sun, start with only 15-20 minutes in the sun on your first session. In your following tanning sessions only increase your time by 5-10 minute increments, and monitor your skin regularly to make sure you arenât starting to go red and burn. If tanning on a sunbed, start with 2-3 minutes.
Over 2,000 years, many imperial dynasties and kingdoms built, rebuilt, and extended walls many times that subsequently eroded. The latest imperial construction was performed by the Ming Dynasty (1368â1644), and the length was then over 6,000 kilometers (3,700 miles). This is the wall often referred to when we talk about the Great Wall.
Below we give you the background behind the figures, explaining what is counted as the Great Wall, and how the length of the Great Wall has changed through different dynasties. The Official Length: 21,196 km (13,170 mi) After a five-year-long survey, the total length of the Great Wall was measured. On June 5th, 2012, the State Administration of Cultural Heritage announced that the official length of the Great Wall is 21,196.18 km (13,170.7 mi). This is the first time that China has scientifically and systematically measured the length of the Great Wall. It's a misleading figure as some sections of different eras were built on top of or right next to each other.